Input Differentiation for Touch Computing Devices

Abstract

Methods for differentiating touch inputs are disclosed. A method detects a touch input by receiving contact at a computing device's touch surface and identifies whether the touch input was received from a stylus based on additional input received from the stylus. The method responds to the touch input, wherein the response differs based on whether the touch input was received from the stylus. The detecting, identifying and responding are performed at the computing device. A stylus has a capacitive tip, a wireless transceiver, and a pressure sensor for determining a pressure level received at the tip. The stylus determines if a pressure level measured by the pressure sensor has reached a threshold, suppresses capacitive output from the tip to a touch surface if it is determined that the threshold has not been reached, and communicates a message to the computing device based on determining that the threshold has been reached.

What is claimed is: 
     
         1 . A computer implemented method comprising:
 detecting a touch input by receiving a physical contact made at a touch surface of a computing device;   identifying whether the touch input was received from a stylus based on additional input received from the stylus; and   responding to the touch input with a response, wherein the response differs based on whether the touch input was received from the stylus; and   wherein the detecting, identifying and responding are performed at the computing device.   
     
     
         2 . The method of  claim 1 , wherein the identifying comprises associating the touch input with one of the stylus, a finger, multiple fingers, and a palm. 
     
     
         3 . The method of  claim 1 , further comprising receiving, from the stylus, a pressure level corresponding to the detected touch input, wherein the identifying comprises identifying whether the touch input was received from the stylus based at least in part on the pressure level. 
     
     
         4 . The method of  claim 1 , further comprising receiving, from the stylus, a pressure level corresponding to the detected touch input, wherein the identifying comprises determining that the pressure level meets a predetermined pressure level threshold associated with the stylus. 
     
     
         5 . The method of  claim 1 , further comprising receiving, from the stylus, a pressure level received via a capacitive tip of the stylus, wherein the identifying comprises determining that the pressure level meets a predetermined pressure level threshold associated with the stylus. 
     
     
         6 . The method of  claim 1 , further comprising determining a contact area corresponding to the detected touch input, wherein the identifying comprises identifying whether the touch input was received from the stylus based at least in part on the contact area. 
     
     
         7 . The method of  claim 1 , further comprising receiving, from the stylus, a second input comprising timing data, wherein the identifying comprises identifying whether the touch input was received from the stylus based at least in part on the timing data. 
     
     
         8 . The method of  claim 1 , further comprising receiving, from the stylus, a second input indicating timing information, wherein the identifying comprises one or more of identifying receipt of the second input as being a within a threshold time span of a time that the touch input was received and identifying a synchronization between a clock of the computing device and a clock of the stylus. 
     
     
         9 . The method of  claim 1 , wherein the additional input is received wirelessly from a wireless transceiver of the stylus. 
     
     
         10 . The method of  claim 1 , wherein the identifying is based at least in part on a determined pressure level reaching a predefined threshold and a timestamp received from the stylus. 
     
     
         11 . A computer implemented method comprising:
 detecting a touch input by receiving a physical contact at a touch surface of a computing device;   determining a pressure level corresponding to the detected touch input;   associating, based at least in part on the pressure level, the touch input with a type of touch input; and   responding to the touch input with a response, wherein the response differs based on the type of the touch input; and   wherein the detecting, determining, associating, and responding are performed by the computing device.   
     
     
         12 . A computer implemented method comprising:
 detecting a first touch input and a second touch input, the first touch input detected by receiving a physical contact at a touch surface of a computing device, the second touch input detected by receiving a second physical contact at the touch surface of the computing device;   associating the first touch input with a first type of touch input and the second type of touch input with a second type of touch input different from the first type; and   responding to first touch input and the second touch input with a response based on the first type and the second type; and   wherein the detecting, determining, associating, and responding are performed by the computing device.   
     
     
         13 . The method of  claim 12 , further comprising identifying a workflow based on the first type and the second type. 
     
     
         14 . The method of  claim 13 , wherein the workflow comprises operations in an application executing on the computing device for at least one of:
 an erasure;   an undo operation;   a redo operation;   a brush size selection;   a brush opacity selection;   a selection of a line angle constraint;   a menu navigation;   a menu selection;   a copy operation; and   a paste operation.   
     
     
         15 . The method of  claim 12 , wherein the associating comprises associating the first touch input with a stylus and associating the second type of touch input with one of a finger, multiple fingers, and a palm. 
     
     
         16 . The method of  claim 12  wherein the detecting comprises detecting that the first touch input and the second touch input occur simultaneously. 
     
     
         17 . The method of  claim 12  wherein the detecting comprises detecting that the first touch input and the second touch input occur sequentially. 
     
     
         18 . A computer readable medium having instructions stored thereon, that, if executed by a processor of a computing device, cause the computing device to perform operations for differentiating input received at a touch surface of the computing device, the instructions comprising:
 instructions for detecting a touch input by receiving a physical contact made at the touch surface of the computing device;   instructions for identifying whether the touch input was received from a stylus based on additional input received from the stylus; and   instructions for responding to the touch input with a response, wherein the response differs based on whether the touch input was received from the stylus.   
     
     
         19 . The computer readable medium of  claim 18 , wherein the instructions for identifying comprise instructions for receiving the additional input as being a within a threshold time span of a time that the touch input was received. 
     
     
         20 . The computer readable medium of  claim 18 , further comprising:
 instructions for detecting a second touch input by receiving a second physical contact made at the touch surface of the computing device;   instructions for determining that the second touch input was not received from another input means different than the stylus based on not receiving additional input from the another input means a within a threshold time span of a time that the touch input was received.   
     
     
         21 . A stylus comprising:
 a capacitive tip configured to interact with a touch surface of a computing device;   a wireless transceiver configured to communicate with the computing device;   a pressure sensor configured to determine a level of pressure received at the tip;   a processor; and   a computer readable medium having logic encoded thereon, that if executed by the processor, cause the processor to perform operations comprising:
 determining if a level of pressure measured by the pressure sensor has reached a predetermined threshold; 
 suppressing capacitive output from the tip to the touch surface if the determining determines that the threshold has not been reached; and 
 communicating a message to the computing device based on determining that the threshold has been reached. 
   
     
     
         22 . The stylus of  claim 21 , wherein the tip is configured to deliver a pressure stream to the computing device, the operations further comprising:
 modulating the pressure stream by delivering the pressure stream in response to determining that threshold has been reached.   
     
     
         23 . The stylus of  claim 21 , wherein the pressure sensor is configured to determine the level of pressure when the tip is in physical contact with the touch surface, the stylus further comprising:
 wirelessly communicating, via the wireless transceiver, one or more of a timestamp corresponding to the physical contact with the touch surface and a timestamp corresponding to the communicating of the level of pressure, to the computing device.